Danfoss VLT HVAC Drive FC 102 Operating Instructions Manual page 98

How to Programme
Damper
Damper
6 6
Damper
Illustration 6.17 Example, Multi-zone, Single Setpoint
Example 2 – Multi-zone, multi-setpoint
The previous example illustrates the use of multi-zone,
multi-setpoint control. If the zones require different
pressures for each VAV box, each setpoint may be
specified in parameter 20-21 Setpoint 1,
parameter 20-22 Setpoint 2 and 20-23 Setpoint 3. By
selecting [5] Multi-setpoint minimum in
parameter 20-20 Feedback Function, the PID controller
increases the fan speed if any one of the feedbacks is
below its setpoint. If all feedbacks are above their
individual setpoints, the PID controller decreases the fan
speed.
20-21 Setpoint 1
Range:
0
ProcessCtrlUnit
96
Supply
air fan
Cooling/
heating coil
Return air fan
Function:
[-999999.999 - Setpoint 1 is used in closed-
999999.999 loop mode to enter a
*
ProcessCtrlUnit] setpoint reference that is
used by the frequency
converter's PID controller. See
the description of
parameter 20-20 Feedback
Function.
NOTICE
The setpoint reference
entered here is added to
any other references that
are enabled (see
parameter group 3-1*
References).
Danfoss A/S © 08/2014 All rights reserved.
Operating Instructions
20-22 Setpoint 2
Range:
0
ProcessCtrlUnit
P P
Zone 1
VAV
Box
P P
Zone 2
VAV
Box
P P
Zone 3
VAV
Box
Function:
[-999999.999 - Setpoint 2 is used in closed-
999999.999 loop mode to enter a
*
ProcessCtrlUnit] setpoint reference that may
be used by the frequency
converter's PID controller. See
the description of
parameter 20-20 Feedback
Function.
NOTICE
The setpoint reference
entered here is added to
any other references that
are enabled (see
parameter group 3-1*
References).
MG11F502